Refrigerating machine condenser



Feb. 1.6, 1937. c. sT'EENsTRUP 2,071,182

REFR-IGERATLNG MACHINE coNDENsER Qriginal Filed Jan. 26, 1935 2 Sheets-Sheet 1` bg )Vd/1% Feb. 1 6, 1937. c. sTEENVsTRuP 2,071,182

' REFBIGERATING MACHINE CONDENSER original Filed Jan. 26, '19:55v 2 sheets-sheet 2 mntof: Chvistom Steenstrupa 'b9 ffm/175; v

Patented Feb.; i6, i937 REFRIGERATING MACHINE CUNDENSER Christian Steenstrup, Schenectady, N. Y., assigino: to General Electric Company, a corporation of New York Claims.

My invention relates to condensers and more particularly to air cooled `condensers for use in refrigerating machines.

This application is a division of my application 5 Serial No. 3,624 filed January 26, 1935, for improvements in Refrigerators and. assigned to the General Electric Company, my present invention.

It is an object of my invention to provide 'an improved air cooled condenser v particularly adapted 'for use in refrigerating machines which occupies a minimum amount of space, which is made of relatively thin and inexpensive sheet metal. n

Another object of my invention is to provide a sheet metal condenser which is sufficiently strong and rigid in construction to form a support for the refrigerant circulatory unit of a refrigerating machine without the use of an extra supporting frame, or the like,

YF'urtherobjects and advantages of my invention will become. apparent as the following-de scription proceeds and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

A better understanding of my invention may be had by reference to the accompanying drawings, in which Fig. 1 is a side elevation, partly in section, of a refrigerating machine provided with a condenser embodying my invention; Fig. 2 is a perspective view of the' condenser of the refrigerating machine shown in Fig. l; Fig..3 is a detailed sectional view of the purging valve provided on the condenser shown in Fig. 2; and Fig.

4 is a perspective view of amodied form of condenser embodying my invention and' which may be substituted for the condenser shown in Figs. l and 2.

Referring to the drawings, in Fig. 1 I have shown a refrigerator of the household type provided with an air cooled natural draft condenser embodying my invention. The refrigerator shown in Fig. 1 is' provided with a cabinet .and a. separable refrigerating machine. The cabinet includes a rectangular outer sheet metal shell I0 having a rectangular opening in the top thereof and is provided with 'an imperforate horizontal sheet metal partition II therein, which extends entirely across the interior of the cabinet. The partition n II divides the space within the rectangular shell I0 into an upper cooling or food storage compartment I4 and a lower machinery compartment I5, respectively. The cooling comthe assignee of partment Il is provided with an open top rectangular inner liner I6 which covers the bottom and side walls thereof and is provided with a rectangular door opening I1 in the front wall thereof. The inner liner I6 is surrounded by heat insulation I8 and the opening I1 in the front Wall thereof is closed by a heat insulated door i9.

The cabinet described above is provided with a separable .refrigerating machine including as its principal elements a refrigerant circulatory unit or compressor, a condensery and a refrigerant expansion unit. In the present embodiment of my invention, the machine is of the compression type. This machine includes as an element a refrigerant liquefaction apparatus comprising a compressor unit 30 having a motor driven compressor contained in a cylindrical hermetically sealed steel casing 3l and also comprising an air cooled sheet metal condenser 32, embodying my inventiomand arranged at the back of the cabinet. The other principal element of the machine is an evaporator 33located within the cooling compartment I4. Gaseous refrigerant is com- -pressed by the compressor unit 30 lqueed in the condenser 32 and vaporized in the evaporator 33- by the absorption of heat from the contents of the cooling compartment I4. The vaporized refrigerant is then returned to the compressor unit 30 and the cycle is repeated. The operationof the apparatus is described more in detail below. The provision yof a refrigerating machine separable from a cabinet ordinarily used therewith and including an evaporator and a refrigerant circulatory unit supported on a sheet metal type condenser without the use of an additional reenforcing or supporting frame forms no part of my present invention, but is 'described and claimed in my copending application Serial No. 3,624, referred to above.

I have provided an air cooled condenser including a plurality of complementary sheet metal portions secured together. at least one of the sheet metal portions having indentations therein cooperating with the other sheet metal portion to form a refrigerant circulatory passage therebetween and the sheet metal portions having transversely extending reenforcing sections formed therein in order to form a relatively rigid and strong construction. In the form of nu invention illustrated in Figs. 1 and' 2, vthe air cooled condenser -32 extends over -'a major portion of the exterior side of the rear wall of the cabinet. I prefer to locate the condenser 32 onv the rear wall of the cabinet as it is usually out of sight there and at the same time receives an adequate supply of cooling air. The condenser l32 is made of inner and outer .portions crjof sheets of metal 34 and 35, which are provided with a series of complementary verticalindentations formed therein, such as the indentations 36 and 3l, best shown in Fig". 2. These vertical indentations form a series of vertical refrigerant` circulatory passages 38, which are connected in parallel relationship at their upper and lower ends by manifolds 33 and 38, respectively. The manifolds 39 and [it are formed by complemen tary horizontal indentations formed in the inner and outer sheets 34 and 35. The sheets 3d and 35 are joined together in face engagement by line welding, or by a series of closely spaced spot welds, extending about the peripheral edges thereof and along the contacting portions thereof between the indentations formed therein through..

out the length of such indentations. The sheets 34 and 35 may be joined together by brazing or in some similar manner. The lower edge of the condenser 32 is bent inwardly forming a horizontal lower strengthening ange di. The cenm ter of the condenser 32 is bowed outwardly thus giving the cross section of the central portion thereof an arcuate shape. The ends of the flange di, such as the end i2 shown in Fig. 2,'are bent upwardly against the adjacent portions of the condenser 32 and the vertical edges of the condenser are then bent outwardly forming beads or nanges At3 and dil, which constitute transversely extending reenforcing sections therein. The condenser 32 is thus formed with a channel shaped cross section, the central portion thereof behig slightly arcuate in shape. The reenforcing nanges di, d3, and till, as well as the arcuate central portion of the condenser 32 insure a. strong rugged construction which is particularly .rigid with respect to lateral bending, even though the metal sheets 3d and 35 be made from comparatively light sheet metal stock. Consequently, it

is unnecessary to provide the conventional strengthening frame for the condenser 32 and a substantial saving in material and weight is ef-f fected. The condenser is provided with a gaseous refrigerant inlet t5 communicating with one of the vertical passages therein in the lower portion of the condenser and a liquid supply connection or outlet 46 communicating with the lower manifold 40. A purge valve 41 is provided on the upper manifold 39. 'I'he construction of this purge valve is shown in Fig. 3;

The compressor unit 30 extends laterally from and is supported by the lower end of the condenser 32 and is rigidly secured thereto by a pair of upper and lower straps 50 and 5|. These straps 50 and 5| each have a central arcuate portion which conforms to and is rigidly secured to the rings 48 and 49. The rearwardly extending feet of the straps 50 and 5| are secured to a pair of vertical channel irons 52 and 53 by bolts 5i.: which pass through suitable holesi55 formed near the upper and lower ends of the channel irons 52 and 53. Laterally extending feet 56 and 51 of the channel irons 52 and 53, respectively, are Welded, or otherwise rigidly secured, to the front face of the condenser 32 between the indentations v36 formed therein.

'Ihe condenser 32 is supported on the exterior side of the rear wall of the cabinet shell I in spaced relation thereto by a series of supports which includes a pair of U-shaped brackets 58 and 59 located adjacent the top of the condenser and on each side thereof. The inner legs of the brackets 58 and 59 are welded, or otherwise secured, to the adjacent portion of the condenser compartment i5.

comme 32. These brackets are provided with rearwardly extending portions S0 and 6|, respectively, which act as bumpers and aid the anges 43 and 44 in protecting the condenser 32 and spacing itfrom an adjacent -Wall or the like. As shown in Fig. 2, the bracket es is 'provided with a relatively small hole 32 lin the outer legl thereof and a. larger 'hole 63 in the inner leg thereof, the latter hole registering with a hole of the same size in the condenser 32. A. machine screw 64, shown in Fig. l, having a head of a smaller diameter than the hole 63, but larger in diameter than the hole 32 is inserted through the hole 63 and engages the rearwall of the shell I0, thus holding the upper end of the condenser 32 firmly in position en the cabinet. The bracket a is? provided withl a small hole 35 in the outer leg thereof which 'is in alignment with a larger hole formed in the vided in the brackets "ed and 59, described above,v

and bolts 38 are inserted through these holes, the heads of the bolts engaging the rear wall of the shell l@ and the rear ange t3 of the partition il as shown in Fig. l. The lower end of the 'condenser is provided with a pair of brackets Gill and 13' having lower vertical-offset portions lli and l2, respectively. These offset portions are provided with bolt holes 13 and i4 therein. Bolts l5 pass through the condenser 32, cylindrical spacers lt and ll, and the holes 13 and ld, and are secured to the removable angle iron 22. The condenser 32 is thus rmly secured to the exterior side of the rear wall of the cabinet and assists in supporting the laterally extending compressor unit 30 within the machinery The front end of the compressor unit 33 is supported by an L-slfiapedv bracket 18 which is welded to the ringsV 48 and 49, the lower end of the bracket 18 being secured to the angle iron 2| by a bolt 19.

The refrigerant evaporator 33 is arranged in A second pair of U-shapedl the cooling compartment I4 and, in the illustra- I which connects the discharge side of the compressor contained in the casing 3| with the inlet 45 of the condenser 32. A flexible conduit 05, made of copper tubing or the like, connects the outlet 49 of the condenser 32 with a. float valve casing 91 and supplies liquid refrigerant thereto. A liquid line |06 connects an outlet of the oat valve casing 91 with therefrigerant circulatory passages of the evaporator 33. A flexible suction conduit |01, made of copper tubing or the like, communicates with the header 82 of the evaporator 33 above the normal liquid -level therein and with the inlet of the compressor contained in the casing 3|. The conduits |05 and |01 thus provide a flexible connection between the evapodenser 32.

aortica the upper rear edge voi. the shell i@ in order to protect the conduits from abrasion.

It is desirable to locate the inlet d5 of the condenser 32 in the lower portion thereof, as illustional design and, as shown in Fig. 3, includes a hollow cylindrical body il@ which is welded to the outer sheet of the condenser 32. A tapered valve element ill is' threaded "to the interior of the valve'bodv im and the tapered portion of the valve element iii is seated firmly against the seat l i2 formed in the valve body i lil. When the valve element iii isunscrewed, gas may escape to the atmosphere past the valve seat M2 vand through a passage H3 formed in the valve element iii. The passages of the condenser 32 may thus be purged of air or the like by opening the valve ill. y.; f

In the operation of the refrigerating machine, described above, gaseous, refrigerant is cornpressed by the motor driven compressor contained in the casing 3 l is discharged therefrom through the conduit tilt, and enters the condenser 32 at the inlet Alb. The compressed gaseous refrigerant in thecondenser 32 is liquefied by the transfer of heat therefrom to the cooling air which passes over the surfaces of the condenser. It will be noted that the condenser 32 is mounted in spaced relation with respect to the rear wall of the cabinet in order that cooling. air may readily pass over both the inner and outer surfaces of the condenser. Cooling air enters the machinery compartment i5 through the bottom thereof and the opening 23 formed in the front part of the inset portion 2l of the mopboard 2t and passes about the cooling ns Sia and the periphery of the compressor casing 3i absorbing heat there?A from. The air leaving the machinery compartment l5 then passes upwardly between the rear wall of the cabinet and the surface of the condenser 32 adjacent the rear wall of the cabinet. The rising warm air Athus sets up a current of cooling air about the condenser 32 and the latter is sumciently cooled by natural draft, it being unnecessary in the machine illustrated to provide a fan orother forced draft cooling apparatus.

f The circulation of cooling air over the surfaces of the condenser 32 is further facilitated in' that the sides of the space between the condenser and the rear wall of the cabinet are left open so that air may circulate in Aa lateral direction there- `through. The refrigerant in the condenser 32,

which is thus liquefied by the transfer of heat therefrom to the surrounding cooling air drains by gravity to the lower manifold di). The liquid refrigerant thus accumulated in the lower manifold t0 is forced through the outlet t6 by the pressure of high kpressure refrigerant vapor in The purging valve d?? is of conven-A unito maintain the header e2 abbut half m11 of liquid refrigerant. The refrigerant circulatory passages 83 are thus flooded with liquid refrigerant. The refrigerant, which is vaporized by thev absorption of heat from the cooling compartment M, is collected in the header B2 above the level of the liquid refrigerant containedtherein and is drawn off to the compressor contained in the casing 3l through the suction conduit Hill, and the cycle is repeated continuously during operation of the machine.

The refrigerating machine described may conveniently be removed from the cabinet in order to facilitate shipping or disassembly and repair thereof. When removing the machine from the cabinet, the bolts tt and i5 are removed as are the machinescrews 6ft, thus freeing the condenser '32 from the rear of the cabinet. The bolt i9 is removed, as Well as the angle iron 22, inorder that the refrigerant circulatory unit 36 may be swung backwardly out of the machinery compartment i5. Since the conduits m5 and mi are flexible, it is possible to swing the condenser 32 and compressor unit 30, which are rigidly connected to gether, to the rear of the cabinet so that the compressor unit 3;@ lis moved out of the machinery compartment i5.. The top liner il@ and the evaporator and float valve structure which is secured thereto may then be moved vertically upf ward out of the cooling compartment ill. The entire refrigerating machine can be thus removed from the cabinet without the necessity of altering or breaking any of the refrigerant connections.

have shown in Fig. 4 a modified form of air cooled condenser 'Ht embodying my invention which may be substituted for the condenser 32 in the refrigerating machine described above, the condenser lill being of approximately the same size as the condenser 32. The condenser Mft is made up of inner and outer portions or sheets of metal H5 and lit which are provided with a series of complementary vertical indentations therein, suchas theindentations Hl and iid. lThese vertical indentations form a series of vertical refrigerant circulatory passages which are connected in parallelrrelationship at their upper and lower ends by manifolds il@ and im, respectively. The manifolds il@ and i2@ are formed by complementary horizontal indentations in the inner and outer sheets M5 and Mt.

The sheets H5 and lit are joined together in face engagement by line welding, or by a series of closely spaced spot Welding, extending about the peripheralr edges thereof and along the contacting portions thereof between the indentations formed therein and throughout their length. The sheets M5 and il@ are then bent in a corrugated form, shown in Fig. 4, both in order to strengthen the condenser structure thus formed and 'in order to increase the surface area thereof without increasing its width. The corrugations formed in the condenser H3 constitute transversely extending reenforcing sections therein. The vertical edges of the condense'x` lili are bent outwardly to form anges E28 and B22 provided with holes 23 and QM therein respectively. Bolts or other securing means may be inserted through the holes G23 and H24 to 'mount the condenser il@ on the exterior side ofthe rear wall of the cabinet. It will be noted that the sides H25 and G26 of the condenser llt arel somewhat longer than the depth of the corrugations formed therein and in this way space is provided for the circulation of cooling air between the rear wall of the cabinet and the adjacent surface of the condenser, as described above in connection with the construction shown in Figs. 1 to 3, inc1usive. The extended sides |25 and |26 of the condenser llt give'the condensermalchannel-shaped cross section` which is particularly strong and serve to 'reenforce the same. A pair of horizontal metal straps |2l and |28 arefwelded or otherwise secured to the tops of the corrugations on the front of the corrugated condenser l le, these straps being provided with holes |25 and |3il, respectively, registering With'similarholes extending through the condenser lill through which bolts are inserted for rigidly supporting a compressor'unit or the like thereon. The straps 82'11" and |28-a1so serve to strengthen the corrugated sheet metal structure. Other horizontal metal straps, such as the strap |3i arranged adjacentthe top of the condenser, may be welded, or otherwise rigidly secured to the rear side of the condenser ||4 in order to further strengthen the same, as well as to protect the rear of the condenser from damage.

' Compressed gaseous refrigerant enters the condenser ||4 through an inlet |32 which communicates with one of the vertical refrigerant circulatory passages formed therein in the lower portion thereof. Condensed liquid refrigerant leaves the condenser IM through an outlet |33 which communicates with the lower manifold |20. A purging valve 41 which is identical' in construction with the purgevalve 41 shownin Figs. 2 and 3 irl connection with the condenser 32 communicates with theupper manifold ||9 of the con- 'desire my invention to be limited to the particular constructions sho/wn. and described and I intend in the appended claims to cover `all modiiications within theA spirit and scope o-f my invention.

What I- c1aim`as new and desire' to secure by Letters Patent of the United States, is:

1. An air cooled condenser including a plurality of complementary sheet metal portions, means for securing' said sheet metal portions together,

at least one of said sheet metal portions having indentations therein cooperating with the other Any non-condensable gases accumulated in the condenser ||,4 maythus be reof said sheet metal portions to form therebetween manifolds at the top and bottom thereof respectively and passages between said manifolds and communicating therewith, said sheety metal portions having transversely extendingreenforcing sections formed therein and extending'throughout opposite edges of said condenserw f `2. An air cooled condenser including a plurality of complementary sheet metal portions, means for securing said sheet metal portions together, at least one of said sheet metal portions having indentations therein forming a` manifold in the lower portion of said condenser and a plurality of-refrigerant circulatory passages communicating with said manifoldffa/nd connected with each other in parallel'relationship, a refrigerant outlet communicating with said manifold, a refrigerant inlet communicating with at least one of said passagesin the lowerportion thereof, and means including a purgevalve communicating with the upper portion of at least one of said passages for removing non-condensable gas entrapped in said passages. v

3. An air cooled condenser including a plural- Y ity' of complementary sheet'rnetal portions, means for securing said sheet metal portions together, at least one of said sheet metal portions having indentations therein cooperating with the other of said sheet metal portions to form manifolds at the top and bottom thereof respectively and passages between said manifolds and communi- Veating therewith, said lsheet metal portions being of channel-shaped,crosssection Y l 4. An air cooled vgon'denser including a pluralqity of complementary sheet metal portions, means for Securingsaid` sheet metal portions together, at least one' of said sheet metal portions portions having indentations therein cooperating with the otherf'of said sheet metal portions to form manifolds at the top and bottom thereof, respectively, and passages between said manifolds and communicating therewith, at least one of said sheet metalportio'ns having a support- 'ing flange formed. thereon.

ection `of the legs of said chan-l 

